Richards, W.J. 1969. An hypothesis on yellowfin tuna 

 migrations in the eastern Gulf of Guinea. Cah . 

 O.R.S.T.O.M. , Ser. Oceanogr. 7:3-7. 



Presented a conceptual model of migration for 

 tropical Atlantic yellowfin: Adult yellowfin 

 enter the Gulf of Guinea to spawn during the 

 warm season. Larvae and juveniles remain 

 there for about one year. That year class 

 moves south to Angola and subsequently re- 

 turns north to warm water. The movement 

 takes place annually until the fish are over 

 two years old, at which time they move west- 

 ward into the central tropical Atlantic. 

 During the warm season adults return to the 

 Gulf of Guinea to spawn. 



KEY WORDS: tuna, yellowfin, bluefin, skip- 

 jack, migration, spawning, temperature. 



Roberts, P.E. 1974. Albacore off the north-west coast 

 of New Zealand, February 1972. N.Z. J. Mar. 

 Freshwater Res. 8:455-472. 



Albacore were taken where surface tempera- 

 tures were between 18.5° and 21.3°C and usu- 

 ally in blue water with bottom depths between 

 45 and 180 m. Fish were mainly 2- to 3-year 

 olds. In 1970 and 1971 fish were taken in 

 warmer waters than in 1972, probably due to a 

 southward extension of the West Auckland Cur- 

 rent. Although catch rates increased with 

 increasing temperatures they were not inter- 

 preted as being related to the subsurface 

 temperature structure. Little or no differ- 

 ence in thermocline depth or intensity was 

 observed . 



KEY WORDS: tuna, albacore, temperature, 

 color/transparency, depth, age, season, cur- 

 rents, upwelling, thermocline. 



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